Liquefaction of Shengli lignite with methanol and CaO under low pressure

The behavior of liquefaction of Shengli (SL) lignite with methanol and CaO in the presence of FeS and tetralin (THN) was studied. The effects of reaction temperature and time on the liquefaction behavior of SL lignite with methanol and CaO were preliminarily investigated. The liquefaction products obtained were analyzed by FTIR spectrum and elemental analysis. The results show that SL lignite liquefaction with methanol and CaO in the presence of FeS is one of the feasible liquefaction methods. This method has some advantages such as the higher liquefied product yields and n-hexane soluble (HS) + gas yield compared to that of liquefaction in H2 atmosphere; and carrying out at lower pressure, which was only one third of that of liquefaction in H2 initial pressure of 5 MPa. The reaction temperature and time significantly affect the liquefied product yields and distributions. The lignite liquefied product yield and gas + HS yield reach to 81.8% and 62% respectively at 400 °C for 2 h, which are significantly higher than those of liquefaction in H2 initial pressure 5 MPa.

► The behavior of liquefaction of Shengli lignite with methanol and CaO in the presence of FeS and tetralin was investigated.
► The liquefaction was carried out at lower pressure (about 4 MPa) at 400 °C.
► The liquefied product yields are significantly higher than those of liquefaction in H2 initial pressure of 5 MPa.